ES6 React Component lifecycle


Known React lifecycle events

The React lifecycle will go through these cycles:

Event ES5 ES6 Description When
Mounting
getInitialState ✓ ✗ Returns initial state Once
getDefaultProps ✓ ✗ Returns initial props Once (cached)
componentWillMount ✓ ✓ your before-component is mounted functionality Once
render ✓ ✓ Returns HTML to render
Example from this component 
<button className="btn btn-primary"
onClick={this.increment}>
Clicked {this.state.count} time{(this.state.count>1 || this.state.count===0) ? 's' : ''}
</button>
 Every time
componentDidMount ✓ ✓ called after component has been rendered in DOM Once
Updating
componentWillReceiveProps ✓ ✓ called before render when props is about to change Prop changes
shouldComponentUpdate ✓ ✓ stop rendering by returning false Before render
componentWillUpdate ✓ ✓ Just before render this method is ivoked Immediately before render
componentDidUpdate ✓ ✓ Just after render this method is ivoked Immediately after render
Unmounting
componentWillUnmount ✓ ✓ Just before the component is removed from DOM Once